1. Field of the Invention
This invention relates in general to pavement cleaning equipment, and more particularly to a compact, mobile unit suitable for propulsion by a detachably engaged automotive vehicle for use in cleaning pavement such as streets, parking lots and the like.
2. Description of the Prior Art
Conventional street sweeping apparatuses as, for example, commonly used by cities, consist of mobile truck-like vehicles integrally provided with disk-shaped rotatable brushes for movement of dirt and debris away from the curb toward the street into the path of the mobile unit for collection. Dust is ordinarily controlled with such devices by use of water which must often be transported on the street sweeping apparatus or some other vehicle. Of course only finite amounts of water can be so supplied, necessitating expenditure of time to stop and refill. Whether carried on the sweeper unit or independently supplied, as from fire hydrants, a great deal of water (which is in short supply in some geographical areas) is required.
Street sweepers of the water using variety are only suitable for use in above-freezing ambient temperatures as use otherwise would create icy, hazardous conditions and contribute to dangerous and expensive pavement breakdown caused by repeated freezing and thawing of water which remains in cracks and pores of the pavement surface. Use of such sweepers without water would necessarily create unacceptable clouds of dust during broom operation. 0f course, such devices also are not suitable for use in certain industrial areas where water would create a risk of electrocution.
An earlier patent issued to Wilkerson, U.S. Pat. No. 4,741,072, describes a cleaner that is a non-self-motivated, compact, lightweight mobile unit adapted for travel along railroad tracks to be cleaned. The cleaner was further provided with front and back pairs of wheels adapted for attachment to railroad tracks and provided with laterally extending blades for scraping debris toward a single transversely mounted broom assembly having wide, curved finger-like broom members for lifting debris toward a transverse feed conveyor for vacuum-assisted movement of the debris toward a hopper. It was designed for use only on railroad tracks and was not designed for, nor capable of, use on pavement surfaces, as, for example, the wheels thereof would gouge ruts into the pavement and the cut outs provided to accommodate rails would be unnecessary for pavement cleaning.
In contrast to standard street sweeping methods a well-known procedure in railroad track cleaning is to manually develop a berm of cinders, slag, and the like on the tracks and adjoining rail area directly in front of the cleaning device to provide a "wall" against which to push debris with such device. This step facilitates collection of the blocked debris by the device, rather than the undesired consequence of pushing some of the debris away and free from the sweeper which occurs when a berm is lacking. Such loss of debris is inefficient as it requires later manual collection. The same result often occurs with ordinary street sweeping units which may knock some clutter away from the direct line of the collection/sweeping device, requiring a second pass, or manual clean up to complete the job. The new sweeper device, as described and claimed below contemplates inclusion therein of a construction which eliminates the need for such manual berm development.
Accordingly, it is among the objects of the present invention to provide an apparatus which is suitable for year-round sweeping of pavement surfaces whether of concrete, asphalt, rock, packed earth or otherwise, regardless of ambient temperatures, and that the apparatus be adapted internally, as with a "berm builder" disposed between paired roller brooms, for especially efficient movement of debris through the apparatus toward a debris containment device.
It is a still further object that the new sweeping apparatus be capable of use in combination with a vacuum and elevator arrangement such as, for example, that described in U.S Pat. No. 4,741,072, previously referred to herein to facilitate removal of debris and dust from the new device as it is operated, without the use of water, so as to reduce hazardous conditions, destruction of pavement and waste of natural resources.
It is further among the objects of the present invention to provide an apparatus having the described features which is non-self-motivational, as lacking locomotive means, but is adapted for attachment and movement by an automotive-type vehicle, both for transport and cleaning of a pavement surface.
It is another object of the present invention to provide such an apparatus, the brooms and brushes of which are capable of adjustment to compensate for wear which occurs through use thereof.
It is yet another object of the present invention having the described features which is further adapted with forwardly mounted circular rotational brushes which may be raised or lowered for selective use thereof and provided with some degree of horizontal "give" to prevent damage to a support arm as such brushes are used along a curb or gutter.
It is a still further object of the present invention to provide such an apparatus having the features stated which is also adapted with an inspection door for convenient observation of and access to at least a portion of the interior of the apparatus.
It is further among the objects of the present invention that the broom or brush portions thereof be capable of being powered by either hydraulic or pneumatic methods.
It is yet another object of the present invention that such apparatus be simple in design and operation so as to be economical to manufacture, maintain and operate by individuals with a minimal degree of training and only a few hand tools.
Other objects will be in part apparent and in part pointed out hereinbelow.
In furtherance of these objects, the present invention is, briefly, an apparatus for automated sweeping of debris from pavement surfaces. The apparatus includes a rigid housing and first and second roller brooms rotatably mounted transversely within the housing spacedly and parallel in relation to each other. The first roller broom is disposed forwardly of the second roller broom, each of the roller brooms being elongated and having right and left ends relative to a position of an operator of the apparatus and extending therebetween. The apparatus is adapted for causing the first roller broom to rotate clockwise, as viewed from the right end thereof, and for causing the second roller broom to rotate counterclockwise as viewed from the right end thereof. A debris outlet connected to a vacuum source for removal of debris from inside of the housing to the exterior thereof is provided, as well as a construction disposed within said housing substantially beneath said debris outlet for focusing movement of debris within the housing toward the debris outlet. A plurality of support wheels are rotatably attached to the housing, and the apparatus is adapted for connecting to a prime mover to thereby permit propulsion of the apparatus along the surface being swept and transport of the apparatus when non-operational.
The apparatus is further adapted for building up a berm of debris within the housing rearwardly of the first roller broom and substantially parallel thereto. The "berm builder" is disposed transversely within the housing and connected thereto between the first roller broom and the second roller broom.
The rigid housing consists of a top wall, a front wall, a rear wall, and left and right side walls forming an open-bottomed enclosure, an interior thereof having a forward portion and an upper rearward portion, and the left and right side walls being substantially parallel to each other. The rigid housing is provided on the interior thereof with a rigid debris deflection plate transversely fixed to the top wall of the housing forwardly and adjacent in relation to the second roller broom so as to be longitudinally substantially coextensive therewith and to angle downwardly toward the second roller broom and away from the top wall of the housing.